Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reconciliation between the U.S. federal statutory tax rate and effective tax rate
Statutory rate	21.00%	35.00%	21.00%	35.00%
State taxes	0.60%	0.70%	0.70%	0.60%
Taxes on foreign earnings	0.80%	(11.40%)	0.10%	(11.40%)
Credits and net operating loss utilization	(1.00%)	(0.70%)	(0.80%)	(0.80%)
Purchased intangible assets	0.30%	1.20%	0.50%	1.30%
Manufacturing deduction	0.00%	(2.00%)	0.00%	(2.10%)
Permanent items	0.30%	0.60%	0.30%	0.70%
Tax reform	(0.60%)	(0.00%)	(0.30%)	(0.00%)
Other	(1.00%)	0.40%	(0.20%)	0.60%
Effective tax rate	20.40%	23.80%	21.30%	23.90%